The present disclosure generally relates to microphone arrays and specifically to optimization of microphone array geometries for direction of arrival estimation.
A sound perceived at two ears can be different, depending on a direction and a location of a sound source with respect to each ear as well as on the surroundings of a room in which the sound is perceived. Humans can determine a location of the sound source by comparing the sound perceived at each ear. In a “surround sound” system, a plurality of speakers reproduce the directional aspects of sound using acoustic transfer functions. An acoustic transfer function represents the relationship between a sound at its source location and how the sound is detected, for example, by a microphone array or by a person. A single microphone array (or a person wearing a microphone array) may have several associated acoustic transfer functions for several different source locations in a local area surrounding the microphone array (or surrounding the person wearing the microphone array). In addition, acoustic transfer functions for the microphone array may differ based on the position and/or orientation of the microphone array in the local area. Furthermore, the acoustic sensors of a microphone array can be arranged in a large number of possible combinations, and, as such, the associated acoustic transfer functions are unique to the microphone array. Determining an optimal set of acoustic sensors for each microphone array can require direct evaluation, which can be a lengthy and expensive process in terms of time and resources needed.